FIG. 1 illustrates a common rope access system used for descent of a user 1 where a descender device 2 engages a working rope 3 for controlled descent, and a fall arrester 4 engages a backup rope 5. If the descender device 2 or other associated equipment fails, the fall arrester 4 automatically brakes on the backup rope 5 to arrest fall of the user 1. There are various fall arrester designs which can be generally categorised as either automatic hands-free followers or back-up manual devices.
In a typical automatic follower there is provided a housing having a hinged gate for enclosing the backup rope. The follower also includes a large cam and lever with a head of the lever coupled to a user's harness via a lanyard and carabiner-style snap hook. If the user falls the lever pivots the large cam which brakes the backup rope within the housing.
In a typical manual device there is provided a primary cam for braking where the user's carabiner and lanyard is connected to a body of the device. The body includes a pivoting cover plate which can be opened for locating the fall arrester on the backup rope. The manual device, on rapid descent of a user, rocks the housing relative to the primary cam for braking of the rope. The manual device also includes a secondary cam and lever which connects to the user's carabiner so that rocking of the housing is promoted by the secondary cam which frictionally engages the backup rope. This style of manual device presents a dropped objects hazard in that it must be detached from the user's carabiner when attaching to the backup rope.
It is to be understood that any acknowledgement of prior art in this specification is not to be taken as an admission that this prior art forms part of the common general knowledge.